Electric lamp and mounting therefor



Marcb17, 193s. 'W J E.G R-HAL 2,034,512

ELECTRIC LAMP AND MOUNTING THEREFOR Filed March 22, 1933 2 Sneaks-Sheet 1 36 [All ENTERS v ML TEA JE'EJEER ALFRED TGASK'ILL THEIR. ATTUR. NE'Y' March 17, 1936. J, GER ET AL 2,034,512

ELECTRIC LAMP AND MOUNTING THEREFOR Filed March 22, 1933 2 Sheets-Sheet 2 [NI "E TER 5 WIL m JG'E'ZEE'R flF'REU. T GASKJLL BY mm THEIR. AT TUANEY' Patented Mar. 17, 1936 v UNITED STATES ELECTRIC LAMP AND MOUNTING THEREFOR I Walter J. Geiger, Cleveland Heights, and Alfred '1.

Gaskill, Cleveland, Electric Company,

Ohio, assignors to General a corporation of New York Application March 22, 1933, Serial No. 662,080 9 Claims. (Cl. 240-41) Our invention relates to mountings for electric lamps and the like, .and is especially adaptable and useful in cases where the light source should occupy a. definite position with reference to some associated part or structure, such as a reflector or a lens. The invention is of particular advantage for projection lamps such as vehicle headlamps, in which an incandescent filament lamp is mounted in a reflector such as the wellknown paraboloid reflector.

In headlampsas at present constructed, the lamp is mounted by inserting its bayonet" base in a tubular bayonet socket which is itself mounted in an opening at the apex of the reflector, with suitable provisions for adjusting the socket relative to the reflector to focus the light source of the lamp to exactly the right position for any desired distribution of light. While this arrangement permits easy removal and replacement of a lamp as well as accurate focusing, yet it is mechanically complicated, and often liable to derangements which allow the lamp to shift out of focus.

To overcome these disadvantages of present practice, we prefer to mount the lamp base more directly on the reflector, without the intervention of a socket and adjusting means therefor. This we do in such away that when a given lamp is once properly focused in a reflector, this adjustment becomes permanently fixed; although the particular lamp can still be removed and replaced as often as desired, for cleaning of the lamp or its reflector, etc. In this way, we are able to dispense with the usual lamp socket, as well as with its focusing mechanism.

For removably mounting the lamp, we provide its base with engagement means adapted to engage in a perfectly definite and fixed relation with an accurately located and fixed part or engagement means of the reflector, provision being also made for holding said base and reflector engagement means in proper engagement, preferably by spring pressure. This requires, of course, that the engagement means on the base be properly adjusted and fixed relative to the light source; and while this may be accomplished by extreme accuracy in the basing of the lamp, yet we prefer to embody the engagement means of the base in a separate part or adapter that can be properly adjusted on the base in focusing and permanently fixed thereto,as by soldering, or other methods of forming a fused joint. For bringing the securing means of base and reflector into proper relations to be held engaged by spring pressure, we prefer axial and rotary movements of the lamp relative to the reflector. Further features and advantages of our invention will appear from the following description of species thereof, and from the drawings.

In the drawings, Fig. 1 is an elevation, partial- 1y sectioned, of a headlamp employing a form of mounting comprising our invention; Fig. 2 is a disassembled perspective view of a mounting and lamp; Fig. 3 is a plan view of an adapter for the base of the lamp; Fig. 4 is a partially sectioned side view of electrical connection means for the lamp; Fig. 5 is a perspective view of a modified part for the lamp mounting; Fig. 6 is an elevation in section of another form of mounting; and Fig. 7 is a rear view of the same.

Referring to Figs. 1 and 2, the lamp, indicated generally by the numeral I0, comprises a bulb I I having a filament I2 sealed therein and mounted on leading in wires I3. A base I4 comprising a tubular shell I 4 is mounted on said bulb I I, and carries a terminal pin I5 mounted in insulating material I6 and protruding beyond the end of said base. One of the leading-in wires I3 is connected to the base shell I 4' and the other is connected to the pin l5. An adapter I! comprising a narrow band or shell having a plurality of projections, such as radially extending lugs or arms l8--I9--2Il, is mounted on the base shell It. (Seealso Fig. 3.) The adapter I! is located on said base l4 so that the lugs I8l9--2Il (or their forward surfaces), which determine the longitudinal position of the base in a reflector, as hereinafter explained, bear a definite relation to the filament I2, the adapter I! being of slightly larger diameter than the shell I4 so that the lamp base may be rocked and shifted therein to locate the filament both axially and longitudinally. When the filament has been properly located so as to lie at or near the focus of a reflector when the lamp is mounted therein (as now to be described), this focus adlustment is permanently fixed by fixing the adapter to the base shell I4 preferably by solder 2 I.

The apex of the reflector 22 comprises a flattened portion 23 the back surface of which bears a definite relation to the focal point. The said flattened portion 23 has on opening or hole 24, and slots or notches 25-26-21 in its margin around the opening, to permit the insertion of the lamp lo and adapter n with its lugs; The'hole 24 is preferably just large enough to receive the base I la-or rather the adapter band Il-easily but without any substantial play or looseness. The slot 25 is preferably made wider than slots 26-21 and the lug III of theadapter is preferably made wider than lugs Ill-29, to insure that the lamp l0 shall be properly inserted. Behind the reflector 22 and its slots or notches 25--2621, there is an elastically yielding abutment plate 30 (mounted and actuated as described hereinafter) that presses forward on the lamp base |4 when the base is inserted in the base opening 24 and .pressed rearward. After the lugs |8-|9-2|l have been inserted through the slots or notches 25-26-21 in this way, the whole lamp H! is turned clockwise, so as to engage each of the lugs or arms |8-|9-20 behind the reflector margin 23, between the slot through which such lug was inserted and the next adjustment slot. As the lamp l0v reaches its intended position, a forward-bent tongue 28 on one of the lugs (preferably lug l8) snaps into a recess or slot 29 in the reflector portion 23, thus automatically locking the base in a definite angular position relative to thereflector.

As shown in Figs. 1 and 2, the abutment plate 39 has a flat annular portion 3| whose opening 32 is located at (in approximate axial coincidence with) the reflector opening 24, and is shown of slightly larger diameter than the base M of the lamp- Ill. The lamp base terminal pin |5 extends rearward beyond the abutment 38. A plurality of equidistanly spaced resilient fingers 33, three in the present instance, extend radially outward from said annular portion 3|. Said fingers 33 are retroverted rearward and inward and their ends bent forward, thus forming resilient loops 34, which terminate in narrow tongue portions 35. The forward-bent ends of the spring fingers 33 extend through holes 36 in the wider portions of said fingers adjacent the annulus 3|, and their tongues 35 .are inserted in holes 31 in the flat reflector margin 23, and bent inward. Thus the abutment 38 is spring-mounted on the reflector 22. The resilient loops 34'hold the annular portion 3| yieldingly pressed against the back surfaces of the lugs |8--|920, which in turn are pressed against the back of the flattened portion 23 of the reflector 22. It is desirable to provide a pair of inwardly projecting protuberances 38-39 on the annular portion 3| of the abutment 30 between the slots 21 and 29. The protuberance 3B, which is located adjacent to slot 21, prohibits a counter-clockwise rotation of the lamp l9 after insertion of the lugs |8-|9-2|l through the slots 25-26-21, because the lug 20 would strike it. The protuberance 36, which is located a short distance inside of the slot 29, prevents further rotation of the lamp H! in a clockwise direction when the tongue 28 of lug |8 reaches a positionopposite said slot 29. Thus these stoplugs 36-39 prevent both turning of the lamp l0 in the wrong direction and overturning thereof in the right direction.

Electrical connection to the lamp |ll may be made by a helical spring connector 40 (Fig, 4)

which is slipped over the pin l5 of said lamp.

Said connector forms the subject matter of a separate application of even date by Geiger. Said connector 40 comprises a helical spring 4|, one end of which is clamped on a metal sleeve 42 crimped on the end of the insulating covering 43 of a flexible stranded conductor 44 which is in contact with said sleeve. The said spring 4| is distorted so that the axis thereof is not a straight line or the pin l5 may be distorted. In the preferred form a number of turns 45 at the opposite end of said spring 4| are offset axially with respect to the remaining turns, thus insuring a firm contact of said spring with the pin l5. An insulating covering 46, preferably a soft rubber tube, surrounds the said spring 4|.

In Fig. 1 is shown a complete headlamp, wherein the reflector 22 is located in a housing 41. The said reflector is preferably fastened immovably by a flange 48 thereon and screws (not shown) to the housing 41, and is covered by a lens 49. The conductor 44 extends through an insulating washer 50, mounted in a hole in the housing, to the switching and battery equipment. To remove the lamp l0, it is pushed back against the action of the abutment 30 until the tongue 28 is withdrawn from the slot 29, then turned counterclockwise until the lugs l8-|92|l come opposite the corresponding slots 25-26-21, respectively, and then withdrawn forward. The spring connector 49 and a portion of the conductor 44 are thus pulled through the hole 24 in the apex of the reflector 22 with the lamp |0, after which said connector 40 is removed from the pin |5 on the lamp.

In Fig. 5 is shown a modified form of spring mounted abutment plate 5| comprising a flat annular portion 52 with a hole 53 therein of smaller diameter than the base M of the lamp H]. A plurality of looped spring fingers 54 (three, retroverted forward and inward, being shown) extend radially and forwardly from the portion 52 and have tongues 55 at their ends which engage in the holes 31 in the reflector, thus retaining the abutment 5| in position. When a lamp I0 is inserted in the reflector, the back surface of the base |4 engages the portion of the annular surface adjacent to the hole 53, thus causing the abutment plate to push forwardly on said base l4, which in turn causes the lugs |8-|9--26 to be held firmly against the flattened portion 23 of the reflector 22. The terminal pin l5 of the base |4 extends rearward through the opening 53 beyond the abutment 5|,

The modification shown in Figs. 6 and '7 resembles that of Figs. 1 and 2 in that the annular abutment plate 56 is yieldingly spring-pressed against the rear of the reflector portion 23 or against the rear sides of the lugs |8-|9-28, when the lamp is in place. For this purpose, a plurality of helical compression springs 51 (three being shown) are mounted on guide studs or pins 58 that extend loosely through guide openings (holes) 59 in the plate 56. The springs 51 act against washers 60 retained on the pins 58 by flattened portions 6| at their rear ends. As shown, the pins 58 have integral heads in front of the reflector portion 23, and extend loosely through holes 62 in the latter.

What We claim as new and desire to secure by Letters Patent of the United States, is:

l. The combination with a reflector having a flattened or plane portion at the apex thereof with a lamp base opening therein and a plurality of notches in the flat reflector margin around said opening; of a lamp with a base for' said opening having lateral projections, corresponding to said notches, for engaging the back of the reflector margin between the notches when the base is turned in the reflector after insertion of its projections through said notches; and a spring member carried by and located behind the reflector and the projections, directly engag ing the rear surfaces of said projections and yieldingly pressing them forward against the back of said reflector.

2. The combination of a reflector having a lamp base opening therein, with a plurality of notches in the reflector margin around said open aosama a lamp base inserted and pressed rearward in' said opening; a lamp with a base for said opening having projections, corresponding to said notches, for engaging the back of the reflector margin between the notches and thereby maintaining the base in definite relation to the reflector when the base is turned in the opening after insertion of its projections through said notches;

means for automatically locking said base in the proper angular position relative to said reflector; and means for preventing both turning of the lamp base in the wrong direction after insertion of its projections through the notches, and overturning thereof in the right direction.

3. The combination of .a reflector having a lamp base opening therein, with a plurality of notches in the reflector margin around said opening; means for yieldingly pressing forward on a lamp base inserted and pressed rearward in said opening; a lamp with a base for said opening having projections, corresponding to said notches, for engaging the back of the reflector margin between the notches and thereby maintaining the base in definite relation to the reflector when the base is turned in the opening after insertion of its projections through said notches, but insertable through the notches as aforesaid in only one angular relation of base and reflector; and means for automatically locking said base angularly relative to said reflector when said projections are engaged with its margin just to one side of the notches through which inserted.

4. The combination of a reflector having a lamp base opening therein, witha plurality of notches in the reflector margin around said opening; means for yieidingly pressing forward on a lamp base inserted and pressed rearward in said opening; a lamp with a base for said opening having projections, corresponding to said notches, for engaging the back of the reflector margin between the notches and thereby maintaining the base in definite relation to the reflector when the base is turned in the opening after insertion of its projections through said notches, but insertable through the notches as aforesaid in only one angular relation of base and reflector; means for automatically locking said base angularly relative to said reflector when said projections are engaged with its margin just to one side of the notches through which inserted; and means for preventing both turning of the lamp base in the wrong direction after insertion of its projections through the notches, and overturning thereof in the right direction.

5. The combination of a reflector having a flattened or plane portion at the apex thereof with a. lamp base opening therein and a plurality of notches in the flat reflector margin around said opening; an elastically yielding abutment behind said reflector, apertured at said lamp base opening thereof, for pressing forward -on a lamp base inserted and pressed rearward in said opening; a lamp with a base for said opening having projections, corresponding to said notches, for engaging the back of the reflector margin when the base is turned in the opening after insertion of its projections through said notches, and also having a terminal pin to extend rearward behind said abutment; and a current supply conductor for said lamp, with a connector for said pin.

6. The combination of, a reflector having a lamp base opening therein, with three notches in the reflector margin around said opening, and a recess or opening between two of said notches; means for yieldingly pressing forward on a lamp base inserted and pressed rearward in said opening; and a lamp with a base for said opening having three arms, corresponding to said notches, distributed therearound, for engaging the margin of said opening between the notches when the base is turned in said opening after insertion of its said arms through said notches, one of said arms. having thereon a projection for engaging in said recess or opening so as to lock said base in definite angular relation to said reflector.

'7. The combination of a reflector having a flattened or plane portion at the apex thereof with a lamp base opening therein and a plurality of notches in the flat reflector margin around said opening, and abutment means for yieldingly pressing forward on a lamp base inserted and pressed rearward in said opening; a lamp with a base for said opening having projections, corresponding to said notches, for engaging the back of the reflector margin around the opening when the base is turned in the opening after insertion of its projections through said notches, and also having a terminal pin arranged to extend rearward behind said abutment means; and a current supply conductor for said lamp base having a connector for said pin.

8. The combination of a reflector having a lamp base opening therein with a plurality of notches in the reflector margin around said opening, a lamp with a base for said opening having projections corresponding to said notches for engaging the back of the reflector margin between the notches and thereby maintaining the base in definite relation to the reflector when the base is turned in the opening after insertion of its pro jections through said notches, and an abutment plate behind said reflector over said notches apertured at said lamp base opening of the reflector and having retroverted radial spring fingers with their ends secured to the reflector, a portion of said lamp base extending through said aperture in said abutment plate, said abutment plate directly engaging said lamp base projections and yieldingly pressing them against the back of said reflector margin.

9. The combination of a reflector having a lamp base opening therein with a plurality of notches in the reflector margin around said opening, a lamp with a base for said opening having projections corresponding to said notches for engaging the back of the reflector margin between the notches and thereby maintaining the base in definite relation to the reflector when the base is turned in the opening after insertion of its projections through said notches, and an abutment plate behind said'reflector over said notches apertured at said lamp base opening of the reflector, a portion of said lamp base extending through said aperture in said abutment plate, guides extending rearward from said reflector through guide openings in said abutment, and compression springs mounted on said guides behind said plate, said plate engaging said lamp base projections and yieldingly pressing them against the back of said reflector margin.

- WALTER J. GEIGER.

ALFRED T. GASKILL. 

